1. Field of the Invention
This invention relates to an apparatus for facilitating the use of tools, such as tools for the removal and installation of tee caps, couplings and the like on underground pipeline systems, and tools for performing other operations, such as surface preparations including cleaning and beveling of the ends of plastic pipe prior to the insertion of a coupling or end cap, on underground pipeline systems. More particularly, this invention relates to an apparatus for facilitating the use of tools in performing operations on underground pipeline systems in which visibility and access to the underground pipeline systems are limited.
2. Description of Related Art
Gas utilities perform several operations on underground pipeline systems including the removal and installation of tee caps, insertion of couplings and pipeline surface preparations. When performed through a traditional bell hole, the performance of these operations generally does not represent a significant problem. For example, when removing and installing tee caps, workers are able to easily determine the cap size, type of cap and other physical attributes of the cap and are able to access the cap with cap-specific tools/accessories or with common adjustable tools. However, performance of these operations through a keyhole is substantially more problematic.
“Keyholing” and “potholing” refers to the excavation of a hole to access or repair utilities. Potholing and keyholing are preferred over other techniques such as digging shovels, backhoes, and the like which often result in damage to the utilities and the corresponding demand for expensive repair and reconstruction. In addition to the increased costs associated with damage repair and increased labor costs associated with digging, such damage may present danger to workers or others in the immediate vicinity of the excavation.
Typically, a keyhole is 12-18 inches in diameter and up to about ten feet in depth and visibility down the keyhole is limited, thereby precluding the use of conventional tools to access the utility. For removal and installation of tee caps, limited visibility makes it very difficult to determine the type of cap, the cap size and whether or not the workers have the proper equipment to handle the cap. In addition, tee cap designs are not standardized. Thus, it is extremely difficult to identify every variation in cap design and size and to have specific tools and accessories for each design and size. Frequently, the type of cap is not even known until it is unearthed. It is, thus, apparent that for a crew truck to be equipped for every possible cap design would require an excessive amount of tools and accessories. Accordingly, a tool for removal and installation of tee caps in keyholes, or even in conventional bell holes, which is able to accommodate a majority, if not all, of the various cap designs and sizes would be highly desirable.
Similar considerations exist in connection with the performance of other operations and procedures on the underground pipeline through keyholes and potholes as well.